Current failure indicator



March 29, 1960 H. G. WALTERS 2,931,019

' CURRENT FAILURE INDICATOR Filed Aug. 1. 1957 \31 42 39 44, I Q ac 4s A L INVENTOR.

HENRY 6, WALT 5R5 ATTORAEY CURRENT FAHLURE INDZCATOR Henry G. Waiters, Phoenix, Ariz. Application August 1, 1957, Seriai No. 675,535

ll Ciaim. (Ci. 349-253) This invention pertains to improvements in current failure indicators.

One of the objects is to provide a self-contained unit which may be plugged into a convenience outlet to automatically give an indication of current failure or interruption so that time clocks on the circuits and other apparatus may be reset.

Another object is to provide in the recited device, a means to automatically render the device inoperative should it be removed from the convenience outlet.

Further features and advantages of this invention will appear from a detailed description of the drawings in which:

Fig. l is a schematic diagram of one form of the apparatus incorporating the features of this invention.

Fig. 2 is a schematic diagram of another form of the apparatus having the features of this invention.

As an example of one embodiment of this invention there is shown a unit 9 having an electric plug 1% fixed thereto including the prongs 11 for insertion in the usual convenience outlet (not shown) of the 110 volt A.C. lighting circuit. Each of the prongs 11 are connected through leads l2 and 13 to a solenoid coil 14 of a relay 15 so as to maintain the contacts 16 and 17 open so long as the coil 14 is ener ized. A suitable tension spring 18 serves to close the contacts 16 and 17 when the coil 14 is deenergized.

A plunger 19 axially slidable in the plug it} has its inner end 29 in engagement with the contact arm 21 of the switch 22 so that when the unit is plugged in the outer end 23 of the plunger 19 engages the face of the convenience outlet to close contacts 24 25. A suitable battery 25a is connected by a lead 26 to the contact arm 21 or" the switc 22 while the other terminal or" the battery 25 is connected by a lead 27 to a suitable warning device such as the hell 28. The bell in turn is connected by a lead 29 to the contact arm 38 of the switch 15. Contact arm 31 of the switch 15 is connected by ead 32. to the contact arm 33 of the switch 22.

When the unit 9 is pulled from the convenience outlet, contacts 24 and 25 open so that the battery cannot energize the warning bell, even though contacts 16 and 17 are closed at this time. With the unit 9 plugged in closing contacts 24 and 25, should power failure occur, coil 14 becomes deenergized closing contacts 16 and 17 causing warning bell 28 to be energized.

Still another arrangement is that shown in Fig. 2 wherein the unit 34 has a plug 35 fixed thereto having prongs 36 for insertion in the usual convenience outlet (not shown). A clock mechanism of usual construction having an escapement (not shown) and the main winding drum 37 journaled in the unit 34 and interconnected therewith by the usual main spring (not shown) which normally rotates the drum in the direction indicated by 2,931,019 Fatented Mar. 29, 1960 the arrow 38 has a ratchet wheel 39 fixed thereto. The ratchet wheel has a bore 40 including a series of notches M in which a pin 42 fixed on the end of the plunger 43 engages, the plunger 43 being normally yieldingly urged by the compression spring 44 to engage the pin in a slot il to prevent unwinding of the drum 37. A ratchet plungor 45 suit-ably slidably mounted in the unit 34 is normally yieidingly withdrawn from the ratchet Wheel by a tension spring 46 connected between the plunger 45 and the unit A solenoid coil 47 surrounding the plunger 45 is adapted when energized to hold the plunger 45 into engagement with the ratchet wheel 39 preventing unwinding of the drum 37. The solenoid coil is connected by leads 48 and 49 to the prongs 36. Suitable warning apparatus such as hell ringing mechanism of conventional type (not shown) may be connected to the rotating drum 3! as desired.

When the unit 34 is plugged in, coil 47 is energized holding plunger 45 in engagement with the ratchet wheel and this condition prevails so long as coil 47 remains energized from prongs 36. Also, as the unit is plugged in the outer end it? of the plunger 43 engages the face of the convenience outlet (not shown) compressing spring to release the pin from a notch 41 to condition the drum 39 for free rotation. Should a current interruption occur when the unit is plugged in coil 47 is deenergized allowing spring 4-6 to withdraw plunger 35 starting drum 37 rotating to actuate the warning device connected to the drum.

While the apparatus herein disclosed and described constitutes a preferred form of the invention, it is also to be understood that the apparatus is capable of mechan ical alteration without departing from the spirit of the invention and that such mechanical arrangement and commercial adaptation as fall Within the scope of the appendent claim are intended to be included herein.

Having thus fully set forth and described this invention what is claimed and desired to be obtained by United States Letters Patent is:

In a current failure indicator unit, a plug having prongs for insertion in a. convenience outlet, a rotatable winding drum, a series of stop notches in said drum, a plunger in said plug adapted to engage the face of a convenience outlet and having a pin adapted to engage said notches, means in'said unit to engage said pin in said notches to prevent rotation of said drum when said unit is unplugged from the outlet, a ratchet wheel fixed to said drum, a ratchet plunger adapted to engage said ratchet wheel to prevent rotation of said drum, a solenoid coil around said ratchet plunger connected to said prongs to hold said ratchet plunger into engagement with said ratchet wheel when energized from said prongs, and means in said unit for normally withdrawing said ratchet plunger from said ratchet wheel when said solenoid coil is deenergized during power failure.

References Cited inthe file of this patent UNITED STATES PATENTS 2,566,697 Cass Sept. 4, 1951 2,794,803 Crowley et al. Mar. 22, 1955 2,728,823 Auth Dec. 27, 1955 2,759,177 Hightower Aug. 14, 1956 2,768,234 Popp Oct. 23, 1956 2,826,652 Piplack Mar. 11, 1958 FOREIGN PATENTS 12,225 Great Britain May 20 1911 

